Stephen Venn

Carabid beetle assemblages (Coleoptera, Carabidae) across urban-rural gradients: an international comparison

We studied communities of carabid beetles in residual forest patchesalong urban-suburban-rural gradients in three cities (Helsinki, Finland; Sofia,Bulgaria and Edmonton, Canada) to examine their responses to urbanisation. OnlyFinnish carabids showed a marked division of community structure along thegradient. In Bulgaria and Canada, carabids did not separate into distincturban,suburban and rural communities. Our results provide some support for thepredictions that species richness will decrease, that opportunistic specieswillgain dominance, and that small-sized species will become more numerous underdisturbance such as that provided by urbanisation. The rather weak and variedresponse of carabids to this disturbance suggests that local factors and theirinteraction are of primary importance for community composition. Occurrence ofreasonably similar carabid communities across the gradient at each of the threelevels of urbanisation suggests that habitat changes commonly associated withurbanisation have not affected the ecological integrity of carabid assemblagesin residual urban forest patches.

Forty years of carabid beetle research in Europe – from taxonomy, biology, ecology and population studies to bioindication, habitat assessment and conservation

Abstract ‘Carabidologists do it all’ (Niemelä 1996a) is a phrase with which most European carabidologists are familiar. Indeed, during the last half a century, professional and amateur entomologists have contributed enormously to our understanding of the basic biology of carabid beetles. The success of the field is in no small part due to regular European Carabidologists’ Meetings, which started in 1969 in Wijster, the Netherlands, with the 14th meeting again held in the Netherlands in 2009, celebrating the 40th anniversary of the first meeting and 50 years of long-term research in the Dwingelderveld. This paper offers a subjective summary of some of the major developments in carabidology since the 1960s. Taxonomy of the family Carabidae is now reasonably established, and the application of modern taxonomic tools has brought up several surprises like elsewhere in the animal kingdom. Progress has been made on the ultimate and proximate factors of seasonality and timing of reproduction, which only exceptionally show non-seasonality. Triggers can be linked to evolutionary events and plausibly explained by the “taxon cycle” theory. Fairly little is still known about certain feeding preferences, including granivory and ants, as well as unique life history strategies, such as ectoparasitism and predation on higher taxa. The study of carabids has been instrumental in developing metapopulation theory (even if it was termed differently). Dispersal is one of the areas intensively studied, and results show an intricate interaction between walking and flying as the major mechanisms. The ecological study of carabids is still hampered by some unresolved questions about sampling and data evaluation. It is recognised that knowledge is uneven, especially concerning larvae and species in tropical areas. By their abundance and wide distribution, carabid beetles can be useful in population studies, bioindication, conservation biology and landscape ecology. Indeed, 40 years of carabidological research have provided so much data and insights, that among insects - and arguably most other terrestrial organisms - carabid beetles are one of the most worthwhile model groups for biological studies.

Urban dry meadows provide valuable habitat for granivorous and xerophylic carabid beetles

Insect and plant assemblages of dry meadow habitats have declined dramatically since the late nineteenth century due to changes in grassland management practices and the resultant overgrowth of these with nitrophilic vegetation in Finland. The Municipality of Helsinki is committed to developing strategies for the maintenance of urban biodiversity, and networks of meadow habitats provide a potential opportunity for conserving declining plant and insect taxa. We showed that urban dry meadows are important habitats for carabid beetle diversity. Dry rocky meadows and managed sheep’s fescue type dry meadows had greater species diversity, more xerophilic species, granivores and autumn-breeding species than matrix grassland habitat. Many open habitat carabid species collected in our study are granivorous and some are known to predate on seeds of abundant generalist plant species. These carabid species may contribute to the maintenance of plant diversity by controlling dominant species. To further enhance urban biodiversity, we recommend (1) the supplementation of dry meadow networks by the appropriate management of existing meadows and potentially supplementary open habitats, (2) the expansion of these by clearing adjacent scrub and secondary woodland (subject to their potential conservation value) and (3) the retention of open vegetation, avoiding its replacement with asphalt. We also recommend the use of habitat creation, such as the construction of dry meadow habitats on landfill hills, traffic noise barriers or green roofs, to further supplement dry meadow networks.

Conservation value, management and restoration of Europe's semi-natural open landscapes

Abstract Most semi-natural open habitats in Europe have been traditionally maintained by anthropogenic activities, such as grazing or mowing, preventing the establishment of woody vegetation. These habitats harbour a remarkably rich biodiversity in terms of both plant and animal species, but are also highly threatened, mainly by agricultural intensification and land abandonment. With this Editorial we introduce a Special Issue initiated by the European Dry Grassland Group (EDGG) at the Open Landscapes Conference (Hildesheim, 2013) and the 11th European Dry Grassland Meeting (Kulikovo Pole, 2014). We aim to give a short introduction to the current conservation status, significance and research of semi-natural open habitats in Europe and present the collected articles of the Special Issue. These papers cover a wide range of different semi-natural open habitats, including wood-pastures, heathlands, steppes, semi-dry and dry grasslands across the Palearctic region and address issues related to the assessment methods, threats, management and restoration of these habitats. We conclude that, in order to ensure their conservation and to monitor the changes in open habitats, integrative approaches are needed that take into account not only vegetation records, but also multiple animal taxa, abiotic factors, management practices, ecosystem services and modelling simulations for anticipating possible future scenarios. We also recommend that decision-makers should support actions to conserve open habitats in Europe by addressing such major challenges as the encroachment of woody vegetation. We are convinced that the present Special Issue will contribute to a better understanding of ecosystem functions and support the biodiversity conservation and management of semi-natural open habitats. Izvleček Večino pol naravnih odprtih habitatov v Evropi tradicionalno vzdržuje s svojim delovanjem človek, kot na primer s pašo ali košnjo, in tako preprečuje zaraščanje z lesnato vegetacijo. Ti habitati so biodiverzitetno zelo bogati z rastlinskimi in živalskimi vrstami, vendar tudi močno ogroženi zaradi intenzifikacije kmetijstva in opuščanja obdelave. V uvodu želimo predstaviti posebno številko revije, ki jo je vzpodbudila Evropska skupina za suha travišča (EDGG) na konferenci Open Landscapes (Hildesheim, 2013) in na 11. srečanju skupine (Kulikovo Pole, 2014). Predstaviti želimo trenutni varstveni status, pomen in raziskave pol naravnih odprtih habitatov v Evropi in zbrane članke v posebni številki. Ti članki obravnavajo širok nabor različnih pol naravnih odprtih habitatov, med njimi gozdne pašnike, resave, stepe, pol suha in suha travišča palearktične regije in obravnavajo metode njihove presoje, njihovo ogroženost, gospodarjenje in obnovo. Zaključimo lahko, da moramo poleg vegetacijskih popisov upoštevati tudi številne živalske vrste, abiotske dejavnike, načine gospodarjenja, ekosistemske usluge in modeliranje predvidenih možnih prihodnjih scenarijev, če želimo zagotoviti njihovo ohranjanje in spremljanje sprememb. Predlagamo tudi, da nosilci odločanja podprejo prizadevanja za ohranjanje odprtih habitatov v Evropi z obravnavanjem tako velikih izzivov kot je zaraščanje z lesnato vegetacijo. Prepričani smo, da bo posebna številka prispevala k boljšemu razumevanju ekosistemskih funkcij in omogočila ohranjanje biodiverzitete in gospodarjenje spol naravnimi odprtimi habitati.

Management mitigates the impact of urbanization on meadow vegetation

Urban regions often contain remnants of ecologically valuable habitats. Whilst meadow habitats have been recognized as ecologically important and much studied, little attention has been given to meadow assemblages of urban locations. We studied the effects of meadow type, urbanization level, and management on vascular plant species richness, field layer diversity and soil chemistry in 18 grassland sites in the Helsinki Metropolitan Area (60°E, 25°N), on the southern coast of Finland during the summer of 2007. We recorded a total of 252 species, though the average number of species per m2 was only 12.6. The negative effects of urbanization on forbs seemed to result in particular from increased soil nitrate (NO3- -N) concentration. The highest NO3- -N and Fe concentrations and ratios of total inorganic nitrogen (Ntot) to phosphorus (P) and potassium (K), were recorded from the soils of urban rocky meadows. Management by mowing decreased soil NO3- -N and Fe concentrations, ratios of Ntot:P and Ntot:K, and increased species richness and diversity. Elevated NOx deposition is considered as a major driver of urbanization effects on vegetation, though changes in soil pH and metal concentrations, such as zinc (Zn), may also negatively affect the frequency of both forbs and grasses. This study shows that regular management by mowing and removal of hay mitigates these effects. We also recommend increasing the provision of dry meadows and maintaining more areas of supplementary semi-natural grassland habitats in urban green space as concrete measures for the conservation of dry meadow assemblages and urban biodiversity.

Ecology and Conservation of Steppes and Semi-Natural Grasslands

Abstract Palaearctic grasslands encompass a diverse variety of habitats, many of high nature value and vulnerability. The main challenges are climate-change, land-use change, agricultural intensification and abandonment. Many measures are in place to address these challenges, through restoration and appropriate management, though more work is necessary. We present eight studies from China/Germany, Greece, Kazakhstan, Russia and Ukraine. The papers cover a wide range of grassland and steppe habitats and cover vegetation ecology, syntaxonomy and zoology. We also conducted a systematic search on steppe and grassland diversity. The greatest number of studies was from China, followed by Germany and England. We conclude that the amount of research being carried out on Eurasian grasslands is inadequate considering their high levels of biodiversity and vulnerability. We hope to encourage readers to address current major challenges, such as how to manage grasslands for the benefit of diverse taxa, to ensure that conservation initiatives concentrate on sites where there is good potential for success and for the generation of realistic and viable conservation strategies.

The challenge of abandonment for the sustainable management of Palaearctic natural and semi-natural grasslands

Abstract Disturbance by biomass removal is a crucial mechanism maintaining the diversity of Palaearctic grasslands, which are unique biodiversity hotspots. The century-long traditional land use of mowing, grazing and burning, has been fundamentally changed in many parts of the Palaearctic. Due to socio-economic changes, large areas of former pastures and meadows have been abandoned, leading to a succession towards secondary scrublands or forest and the encroachment of competitor grass species, all leading to a decrease in biodiversity. Here we report the causes and consequences of the cessation of traditional grassland management regimes, provide strategies for reducing the impact of abandonment and consider these from the perspective of sustainability. We consider the possibilities for initiating sustainable management regimes in the contemporary socio-economic environment, and discuss the prospects and limitation of alternative management regimes in the conservation of grassland biodiversity. These themes are also the core topics of this Special Feature, edited by the EDGG. We hope that this Special Feature will encourage steps towards more sustainable strategies for the conservation of Palaearctic grasslands and the integration of the sustainability perspective into their conservation.

The Eurasian Dry Grassland Group (EDGG) in 2015–2016

The Eurasian Dry Grassland Group (EDGG, formerly known as European Dry Grassland Group) is an official working group of the International Association for Vegetation Science (IAVS) and was founded in 2008. The EDGG is a network of currently 1141 members from 64 countries (26 July 2016), interested in Palaearctic natural and semi-natural grasslands from any point of view, including fauna, flora, vegetation, ecology biodiversity, conservation, land use and management. The main activities of the EDGG (see Vrahnakis et al. 2013) are (i) the facilitation of international communication between researchers, site managers, policy and decision-makers; (ii) coordination of scientific and policy-related actions in grassland research, conservation and restoration in the whole Palaearctic; (iii) promotion of the development of databases for grassland classification, best-practice in conservation and restoration; (iv) organisation of annual events, such as the Eurasian Grassland Conferences (EGCs) and Field Workshops (formerly known as EDGG Research Expeditions); and (v) dissemination of research results in Special Features of peer-reviewed international journals such as Agriculture, Ecosystems & Environment (Dengler et al. 2014), Biodiversity and Conservation (Habel et al. 2013, Török et al. 2016), Applied Vegetation Science (Dengler et al. 2013), Plant Biosystems (Janišova et al. 2011), Tuexenia (e.g. Becker et al. 2016) and Hacquetia (e.g. Valkó et al. 2016). Whilst we are affiliated to the IAVS, our scope is not restricted to just vegetation science but also includes all taxa that are associated with grasslands. Further information about the EDGG can be found from our web-site at http://www. edgg.org/. You can also find us on Facebook: EDGG Eurasian Dry Grassland Group. This contribution aims at summarising the major developments in the EDGG since the last report (Carboni et al. 2015). The EDGG has undergone a number of fundamental changes during 2015. First of all, whilst we are still the EDGG, “EDGG” now stands for ‘Eurasian Dry Grassland Group’, in place of the previous ‘European Dry Grassland Group’. This reflects a broadening in our geographical scope that has been evident for a considerable time, with active contributions from North Africa, the Near East and Central Asia. The grassland biome extends eastwards far beyond the borders of Europe, and our interest and activities certainly do not end at the European border. The scope of the EDGG has also been modified to cover all Palaearctic natural and seminatural grasslands, without the previous restrictions to dry grasslands and to Europe. This latter change is reflected in the sub-title we have added to the name of the organization, “Eurasian Dry Grassland Group – Grassland Research and Conservation”.